Run 2to3 only for Python 3 and add pyflakes back in
Run 2to3 only for Python 3 and add pyflakes back in

jdc0589/troposphere,craigbruce/troposphere,wangqiang8511/troposphere,cryptickp/troposphere,samcrang/troposphere,garnaat/troposphere,ccortezb/troposphere,yxd-hde/troposphere,mhahn/troposphere,Hons/troposphere,horacio3/troposphere,7digital/troposphere,7digital/troposphere,pas256/troposphere,cloudtools/troposphere,johnctitus/troposphere,amosshapira/troposphere,iblazevic/troposphere,ikben/troposphere,johnctitus/troposphere,ptoraskar/troposphere,alonsodomin/troposphere,pas256/troposphere,LouTheBrew/troposphere,xxxVxxx/troposphere,dmm92/troposphere,jantman/troposphere,DualSpark/troposphere,nicolaka/troposphere,kid/troposphere,WeAreCloudar/troposphere,mannytoledo/troposphere,Yipit/troposphere,dmm92/troposphere,ikben/troposphere,horacio3/troposphere,micahhausler/troposphere,cloudtools/troposphere,inetCatapult/troposphere,alonsodomin/troposphere,unravelin/troposphere